Proefschrift Universiteit van Amsterdam. / Met lit. opg. - Met samenvatting in het Nederlands.

Up to 85% of cyclists experience repetitive strain injuries (RSI's). During long bouts of repetitive tasks, muscle fatigue may cause mal-alignments in kinematics, having cumulative effects, leading to an RSI. Purpose: The study's purpose was to examine how changes in localized muscle fatigue relate to changes in movement kinematics in highly trained cyclists throughout a full fatigue protocol. Methods: Seven highly trained cyclists participated in a 2 session experiment. Session 1 included a VO2 max test and familiarization trial and Session 2 was the fatigue protocol. Kinematic angles measured were trunk lean, hip, knee, ankle, and knee splay angle. Mean angle (MA) and range of motion (ROM) was calculated for each revolution thought the trial. Muscles monitored were the quadriceps, hamstring, gastrocnemius, and tibialis anterior. EMG median frequency (MDF) for each muscle was calculated for each revolution by averaging MDF for the two halves of each revolution. Cross-correlation analysis was done on MDF and MA data and MDF and ROM data. Results: All subjects exhibited increases in trunk lean and decreases in ankle angle. Non-monotonic changes were observed in trunk lean, ankle, knee splay angle, and among ROM results for all 5 angles. A 1-tailed T-tests for all subjects, revealed that HAM (p = 0.020) and GAS (p = 0.018) exhibited significant muscle fatigue. One-tailed T-tests yielded significantly negative cross-correlation time lags [Greek small letter tau] for trunk lean MA, ROM, and hip MA. Conclusions: Non-monotonic changes are present in kinematics and MDF. Therefore pre vs. post experimental designs cannot quantify fatigue processes. Shifts in trunk lean MA, ROM and hip MA are significantly correlated with preceding decreasing shifts of MDF (indicative of onset of fatigue). / text

MSc (Occupational Therapy), Faculty of Health Sciences, University of the Witwatersrand / Ergonomic interventions, addressing work and lifestyle factors, seem more effective in reducing computer related upper limb repetitive strain injury (RSI).This study considered the efficacy of such a programme on the resolution of RSI symptoms. A cross sectional survey, of 325 computer workers in a medical aid company call centres, in Gauteng, South Africa was used to establish a point prevalence of 30.23% for RSI symptoms, which correlates with those found elsewhere. An occupational therapy ergonomic intervention was then designed and piloted for efficacy. A randomised control trial conducted on 37 participants with RSI used the programme and computer generated “Break Software”. The six week intervention included the assessment of: three physical outcome measures and lifestyle factors for, the experimental and control groups. Results indicated positive effects on pain, grip strength, and lifestyle factors including feelings of inefficiency, pressure at the end of the day, depression and work capacity, but little extrapolation of ergonomic knowledge to the workplace.

Key clinical features of cumulative trauma disorders include pain, muscle weakness, and tissue fibrosis, although the etiology is still under investigation. Therefore, we first sought to characterize the temporal pattern of altered sensorimotor behaviors and inflammatory and fibrogenic processes occurring in forearm muscles and serum of young adult, female rats performing an operant, high repetition high force (HRHF) reaching and grasping task for 6, 12, or 18 weeks. Palmar mechanical sensitivity, cold temperature avoidance and spontaneous behavioral changes increased, while grip strength declined, in 18-week HRHF rats, compared to controls. Flexor digitorum muscles had increased MCP-1 levels after training and increased TNFα in 6-week HRHF rats. Serum had increased IL-1β, IL-10 and IP-10 after training. Yet both muscle and serum inflammation resolved by week 18. In contrast, IFNg increased at week 18 in both muscle and serum. Given the anti-fibrotic role of IFNg, and to identify a mechanism for the continued grip strength losses and behavioral sensitivities, we evaluated the fibrogenic proteins CCN2, collagen type I and TGFß-1, as well as the nociceptive/fibrogenic peptide substance P. Each increased in and around flexor digitorum muscles and extracellular matrix in the mid-forearm, and in nerves of the forepaw at 18 weeks. CCN2 was also increased in serum at week 18. At a time when inflammation had subsided, increases in fibrogenic proteins correlated with sensorimotor declines. Thus, muscle and nerve fibrosis may be critical components of chronic work-related musculoskeletal disorders. CCN2 and substance P may serve as potential targets for therapeutic intervention, and CCN2 as a serum biomarker of fibrosis progression. TGFß-1 and CCN2 are important mediators of tissue fibrosis by their stimulatory effect on extracellular matrix deposition, with CCN2 functions as a downstream mediator of TGFß-1. Substance P (SubP), a nociceptor-related neuropeptide, has also been linked to tissue fibrosis, although little work has been done to understand whether SubP directly causes fibrotic responses in tenocytes. Therefore, we sought to determine if SubP induces fibroblast proliferation and collagen production via CCN2 signaling directly or through the TGFß-1/CCN2 signaling pathway. We hypothesized that SubP may act directly through CCN2, independently from the TGFß-1/CCN2 signaling pathway, to increase fibroblast proliferation and fibrogenic and extracellular matrix protein production in vitro. To examine this question, we assayed cell proliferation and production of CCN2, TGFB1 and collagen type 1 in vitro using primary tendon fibroblasts (tenocytes) isolated from flexor digitorum tendons, and using rat dermal fibroblasts (RDF). We observed that cells isolated from flexor digitorum tendons that express proteins characteristic of tenocytes (vimentin and tenomodulin) underwent increased proliferation in a dose dependent manner after TGFß-1 treatment, but not SubP treatment, as did RDF cells. TGFß-1 treatment increased CCN2 production in both tenocytes and RDF cells, while SubP induced CCN2 production only in rat tenocytes. Expectedly, TGFß-1 treatment increased collagen expression in each cell type, as did SubP treatment alone using In-cell Western analysis. Interestingly, preliminary data that needs to be repeated showed that SubP treatment of each cell type enhanced TGFß-1 expression, assayed using In-cell Western and traditional western blot analyses. Our findings suggest that both SubP and TGFß-1 have distinct fibrogenic actions on tenocytes and dermal fibroblast and that both may be involved in tendinosis observed in animal models and patients with fibrosis. Inflammatory pain, muscle weakness, and tissue fibrosis are key clinical features of work-related musculoskeletal disorders. So, lastly, we evaluated the effects of therapeutic interventions on behavioral and cytokine changes in muscle, tendon and serum of HRHF rats that performed the reaching and grasping task for 11 weeks. We compared sensorimotor behavioral changes, and flexor digitorum tissue inflammation and fibrosis in rats receiving anti-TNFα therapy prophylactically during the initial training, or anti-TNFα therapy with or without rest as secondary interventions during the HRHF work task. Untreated or saline only treated animals at the end of the initial training period had decreased grip strength, increased mechanical sensitivity, and increased serum and tissue inflammatory cytokines (TNFα, IL-1ß, IL-6 and VEGF), changes prevented by prophylactic anti-TNFα treatment. Regarding the secondary interventions, four weeks of anti-TNFα therapy with or without rest, provided in HRHF task weeks 4-7, was more effective than rest alone for restoring grip strength; no treatments rescued forepaw mechanical sensitivity. Effectiveness of the 4-week anti-TNFα therapy extended to week 11, despite no further drug treatment after week 7, for maintenance of grip strength. Tissue cytokine analysis in week 11 showed that HRHF rats treated with saline had increased IL-18 in serum, muscle and tendon, and trends for increased muscle CCN2. Each treatment, particularly anti-TNF with or without rest, decreased serum and tendon IL-18 and IL-1alpha. Rats receiving combined rest and anti-TNFα therapy also had increased serum IL-10. Thus, similar short-term anti-TNFα therapy may be a potential intervention in WMSDs. These results demonstrate that both Substance P and CCN2 play important roles in the development of fibrosis in muscle and tendon in WMSDs based on our model of repetition reaching and grasping. Using in vitro methods, it was demonstrated that substance P is capable of inducing CCN2 in isolated tenocytes and rat dermal fibroblasts, independent of TGFß-1 signaling, a novel discovery that make suggest new treatments for fibrotic disorders. Finally, anti-TNFalpha treatment successfully prevented behavioral declines and increases in IL-18 in serum and tissues in our rat model when provided during the course of HRHF task performance. Key clinical features of cumulative trauma disorders include pain, muscle weakness, and tissue fibrosis, although the etiology is still under investigation. Therefore, we first sought to characterize the temporal pattern of altered sensorimotor behaviors and inflammatory and fibrogenic processes occurring in forearm muscles and serum of young adult, female rats performing an operant, high repetition high force (HRHF) reaching and grasping task for 6, 12, or 18 weeks. Palmar mechanical sensitivity, cold temperature avoidance and spontaneous behavioral changes increased, while grip strength declined, in 18-week HRHF rats, compared to controls. Flexor digitorum muscles had increased MCP-1 levels after training and increased TNFα in 6-week HRHF rats. Serum had increased IL-1β, IL-10 and IP-10 after training. Yet both muscle and serum inflammation resolved by week 18. In contrast, IFNg increased at week 18 in both muscle and serum. Given the anti-fibrotic role of IFNg, and to identify a mechanism for the continued grip strength losses and behavioral sensitivities, we evaluated the fibrogenic proteins CCN2, collagen type I and TGFß-1, as well as the nociceptive/fibrogenic peptide substance P. Each increased in and around flexor digitorum muscles and extracellular matrix in the mid-forearm, and in nerves of the forepaw at 18 weeks. CCN2 was also increased in serum at week 18. At a time when inflammation had subsided, increases in fibrogenic proteins correlated with sensorimotor declines. Thus, muscle and nerve fibrosis may be critical components of chronic work-related musculoskeletal disorders. CCN2 and substance P may serve as potential targets for therapeutic intervention, and CCN2 as a serum biomarker of fibrosis progression. TGFß-1 and CCN2 are important mediators of tissue fibrosis by their stimulatory effect on extracellular matrix deposition, with CCN2 functions as a downstream mediator of TGFß-1. Substance P (SubP), a nociceptor-related neuropeptide, has also been linked to tissue fibrosis, although little work has been done to understand whether SubP directly causes fibrotic responses in tenocytes. Therefore, we sought to determine if SubP induces fibroblast proliferation and collagen production via CCN2 signaling directly or through the TGFß-1/CCN2 signaling pathway. We hypothesized that SubP may act directly through CCN2, independently from the TGFß-1/CCN2 signaling pathway, to increase fibroblast proliferation and fibrogenic and extracellular matrix protein production in vitro. To examine this question, we assayed cell proliferation and production of CCN2, TGFB1 and collagen type 1 in vitro using primary tendon fibroblasts (tenocytes) isolated from flexor digitorum tendons, and using rat dermal fibroblasts (RDF). We observed that cells isolated from flexor digitorum tendons that express proteins characteristic of tenocytes (vimentin and tenomodulin) underwent increased proliferation in a dose dependent manner after TGFß-1 treatment, but not SubP treatment, as did RDF cells. TGFß-1 treatment increased CCN2 production in both tenocytes and RDF cells, while SubP induced CCN2 production only in rat tenocytes. Expectedly, TGFß-1 treatment increased collagen expression in each cell type, as did SubP treatment alone using In-cell Western analysis. Interestingly, preliminary data that needs to be repeated showed that SubP treatment of each cell type enhanced TGFß-1 expression, assayed using In-cell Western and traditional western blot analyses. Our findings suggest that both SubP and TGFß-1 have distinct fibrogenic actions on tenocytes and dermal fibroblast and that both may be involved in tendinosis observed in animal models and patients with fibrosis. Inflammatory pain, muscle weakness, and tissue fibrosis are key clinical features of work-related musculoskeletal disorders. So, lastly, we evaluated the effects of therapeutic interventions on behavioral and cytokine changes in muscle, tendon and serum of HRHF rats that performed the reaching and grasping task for 11 weeks. We compared sensorimotor behavioral changes, and flexor digitorum tissue inflammation and fibrosis in rats receiving anti-TNFα therapy prophylactically during the initial training, or anti-TNFα therapy with or without rest as secondary interventions during the HRHF work task. Untreated or saline only treated animals at the end of the initial training period had decreased grip strength, increased mechanical sensitivity, and increased serum and tissue inflammatory cytokines (TNFα, IL-1ß, IL-6 and VEGF), changes prevented by prophylactic anti-TNFα treatment. Regarding the secondary interventions, four weeks of anti-TNFα therapy with or without rest, provided in HRHF task weeks 4-7, was more effective than rest alone for restoring grip strength; no treatments rescued forepaw mechanical sensitivity. Effectiveness of the 4-week anti-TNFα therapy extended to week 11, despite no further drug treatment after week 7, for maintenance of grip strength. Tissue cytokine analysis in week 11 showed that HRHF rats treated with saline had increased IL-18 in serum, muscle and tendon, and trends for increased muscle CCN2. Each treatment, particularly anti-TNF with or without rest, decreased serum and tendon IL-18 and IL-1alpha. Rats receiving combined rest and anti-TNFα therapy also had increased serum IL-10. Thus, similar short-term anti-TNFα therapy may be a potential intervention in WMSDs. These results demonstrate that both Substance P and CCN2 play important roles in the development of fibrosis in muscle and tendon in WMSDs based on our model of repetition reaching and grasping. Using in vitro methods, it was demonstrated that substance P is capable of inducing CCN2 in isolated tenocytes and rat dermal fibroblasts, independent of TGFß-1 signaling, a novel discovery that make suggest new treatments for fibrotic disorders. Finally, anti-TNFalpha treatment successfully prevented behavioral declines and increases in IL-18 in serum and tissues in our rat model when provided during the course of HRHF task performance. / Cell Biology

Work-related repetitive strain injury (RSI), one of the work-related musculoskeletal disorders, is the most commonly reported occupational illness, yet the pathophysiological mechanisms are not yet clear. Using our unique RSI animal model, pathophysiological tissue responses can be examined simultaneously with behavioral responses that serve as indicators of sensorimotor function. Studies in humans and with this animal model have shown that prolonged performance of repetitive tasks leads to declines in grip strength and increased of serum pro-inflammatory cytokines, both valuable biomarkers of underlying tissue injuries. Identification of biomarkers would help to elucidate the time course of the inflammatory stage of these disorders and disease progression. Sickness responses/behaviors, normal responses and behaviors occurring as a consequence of infection or illness, are responsible for re-organizing perceptions and actions to enable individuals to respond appropriately to the infection, injury and other illnesses. These behaviors can include malaise, fatigue, increased irritability and social withdrawal, behaviors that can be beneficial when ill for avoiding others and enhancing wellness. However, sickness behaviors can also include depression, sleep disorders and an enhanced perception of illness. Although recent studies have shown that circulating pro-inflammatory cytokines in serum may trigger sickness behaviors, only a few studies have examined if there is an association between work-related musculoskeletal disorders and subsets of sickness behavior; no one to date has elucidated any plausible biological cause of this association. Also, the combined effects of both aging and performance of repetitive tasks needs more evaluation since several epidemiological studies have shown a relationship between advancing age and susceptibility to musculoskeletal disorders. Therefore, using female Sprague-Dawley rats, the aims of this dissertation project are to: 1) To determine if a systemic inflammatory response is maintained long-term in rats exposed to a moderate demand lever-pulling task with high repetition, low force (HRLF) requirements; if aging enhances this systemic inflammatory response and if this response correlates with functional motor declines; 2) To determine if performance of repetitive upper extremity tasks leads to the development of sickness behaviors (weight loss, decreased social interaction and increased aggression); 3) To determine if a relationship between repetitive upper extremity tasks lead to the development of dose- and age-dependent sickness behaviors, and, to determine if increased serum or brain inflammatory cytokines are plausible mechanisms for the induction of sickness behaviors in this model; and, lastly, 4) To determine if prophylactic or secondary systemic treatments with anti-inflammatory drugs (anti--tumor necrosis factor alpha or ibuprofen) reduces sickness behaviors in rats performing a high demand high repetition high force (HRHF) reaching and handle pulling task. This finding would be in further support of an underlying task-induced inflammatory mechanism contributing to these sickness behaviors. In the first study, the relationship between serum and grip strength was examined in aged and young adult rats performing a HRLF task. Serum levels of interleukin 1-alpha (IL-1α), interferon-gamma (IFNγ) and IL-6 were higher in aged rats in general, compared to young adult rats. Each increased more in aged trained-only and 12-week HRLF rats than in young adult trained-only and 12-week HRLF rats. Serum IL-6 showed the greatest increases, with the highest levels observed in aged 12-week HRLF rats. Grip strength declined with task performance in both age groups; however, this decline correlated negatively and only moderately with serum IL-6 levels in aged rats. Thus, aging enhanced a serum cytokine response in general, a response that was even greater with repetitive task performance. Grip strength was adversely affected by task performance in both age groups, but was apparently influenced by factors other than serum cytokine levels in young rats. In the second study, the relationship between sickness behaviors (weight loss, duration of social interaction and aggression towards novel juvenile rats), serum cytokines and brain cytokines were examined in aged and young adult rats that trained to one of two task levels before performing a HRLF task. Decreased duration of social interaction and increased aggression was greater in both young adult and aged rats that trained for 10 min/day for 4-5 weeks to learn a high force (TRHF) task, compared to young adult and aged rats that learned a low force (TRLF) task. TRHF and TRLF rats of both age groups then performed a HRLF task for 6 to 24 weeks, rats termed TRHF-HRLF and TRLF-HRLF, respectively. Declines in social interaction resolved by week 3 in young adult TRHF-HRLF rats, but were still evident in 6-week aged TRHF-HRLF rats (the final endpoint for TRHF-HRLF rats). Significant increases in aggression were observed only in TRHF-HRLF rats, in both age groups. Declines in social interaction were also observed in aged rats performing a TRLF-HRLF task through week 9, but not in young adult TRLF-HRLF rats, even those performing the HRLF task for 24 weeks. These behaviors correlated moderately with increased serum IL-6 observed in the aged task rats (both TRHF-HRLF and TRLF-HRLF) and young adult TRHF-HRLF rats, although serum TNFalpha and IL-1beta also increased with task performance. Increased IL-6 and IL-6 receptor was detected immunohistochemically in brains of aged TRHF-HRLF rats, specifically in ependymal and endothelial cells, as well as glial cells and neurons of the anterior cingulate cortex and paraventricular nucleus. Thus, training to high force, even for a short time period, induced increased sickness behaviors. Aging contributed to increased sickness behaviors in repetitive task rats, and to increased expression of IL6 and IL-6 receptor in several brain regions. In the third study, the relationships between sickness behaviors (duration of social interaction and aggression towards novel juvenile rats), serum cytokines and brain cytokines were examined in young adult rats performing a high repetition high force (HRHF) task with or without anti-inflammatory medications. Rats that trained to high force (TRHF) had decreased duration of social interaction and increased aggression; these behaviors were prevented by prophylactic anti-TNFalpha or ibuprofen treatment. Untreated TRHF rats that went on to perform a HRHF task showed decreased social interaction and increased aggression through week 12; these behaviors were attenuated by secondary anti-TNFalpha and ibuprofen treatments. Untreated HRHF rats had increased serum GroKC, IFN-gamma, IL-1beta, MIP2, MIP3a and TNFalpha. These increases were attenuated after two weeks of anti-TNFalpha treatment in HRHF weeks 5-6, and after 8 weeks of ibuprofen (in HRHF weeks 5-12). The sickness behaviors correlated moderately with increased serum Gro-KC, MIP2 and TNFalpha, and were concomitant with increased IL-1beta immunoexpression in ependymal and endothelial cells in brains of untreated TRHF and HRHF rats. Both treatments reduced the increased brain IL-1beta expression. Thus, sickness behaviors induced by overuse are attenuated by anti-inflammatory interventions that reduce task-induced increases in systemic and brain inflammatory cytokines. In conclusion, both aging and task performance increased serum inflammatory cytokine responses, the latter in an exposure-dependent manner, with a greater serum cytokine response with performance of high force tasks than low force tasks. While grip strength was adversely affected by task performance in both young and aged rats, it was influenced by factors other than serum cytokine levels. In contrast, decreased duration of social interaction and increased incidence of aggression were influenced by task-induced increases in serum and brain inflammatory cytokines, responses attenuated to baseline levels with systemic anti-inflammatory treatments. Sickness behaviors were also dose- and age-dependent, with higher incidence with performance of high force tasks than with low force tasks, and higher incidence in aged rats. We postulate that the higher incidence in aged rats is due to aged-induced brain "inflamm-aging", as they also had increased immunoexpression of IL6 and IL6 receptor in blood brain barrier cells and in glial and neurons of the hypothalamic pituitary axis. / Physical Therapy

The world is constantly changing and workers are forced to adapt to a pace that is more suitable for machines. In the Automotive Industry assembly line workers injuries keeps increasing despite major improvements in recent years. This is due to the cause that the marked demands more goods but to a lower cost. With this in mind, how can we create an aid for assembly line workers that could decrease repetitive strain injuries, facilitate flexibility and reduce the weight load on the workers joints? In this project I have explored the possibility to create new and intelligent aids for the assembly lines with great focus the human body and ergonomics.

The purpose of this thesis is to explore the subject of industrial exoskeleton in accord-ance to the applicability of the technology preventing musculoskeletal disorders within the automotive industry. The modern technology of exoskeletons has a limited field of research and knowledge and is in need to be studied to provide organisations with proper findings for understanding the applicability of the technology. In the auto-motive industry musculoskeletal disorders (MSDs) is one of the most common disor-ders among employees and industries work constantly to decrease and prevent MSDs within their work environments. By conducting literature reviews, the status of exo-skeleton research and development concluded that academic research mostly focuses on technological development of exoskeletons, and not laboratory and/or field testing of currently available industrial exoskeletons. However, through database and website searches, twenty-four available industrial exoskeletons were identified which could be applicable within the automotive industry. Through literature and a case illustration, a number of potential causes for MSDs within the automotive industry were identified and a framework was developed in order to match appropriate available industrial ex-oskeleton to be used in potentially preventing common MSDs. The discussion of the thesis highlights the benefits and challenges of implementing an industrial exoskele-ton within an industry. Proper research on the currently available industrial exoskele-tons is lacking and creates questions of reliability for the technology. However, devel-opment of industrial exoskeletons have shown to focus on prevention of the most common causes of MSDs within industries in their design and development, making the applicability of industrial exoskeletons highly possible.

Introdução: O Código de Processo Civil determina que nos processos judiciais em que a matéria depender de conhecimento técnico ou científico, o juiz será assistido por perito, que produzirá um laudo. Foram analisados 83 laudos de processos judiciais do Tribunal Regional do Trabalho da 2ª Região (TRT-2), referentes a reclamantes com Lesões por Esforços Repetitivos ou Distúrbios Osteomusculares Relacionados ao Trabalho (LER/Dort), que abrangem afecções crônicas do sistema musculoesquelético de origem ocupacional e são decorrentes, dentre outros motivos, da execução de movimentos repetitivos por tempo prolongado e sobrecarga estática, sem que haja tempo para uma recuperação fisiológica. Deveriam abordar os vários aspectos do adoecimento para auxiliar a decisão judicial quanto à existência de agravo à saúde relacionado ao trabalho, assim como sua extensão e repercussões sobre a vida e capacidade laboral do trabalhador. Objetivos: Identificar e analisar, nos laudos, conceitos sobre adoecimento ocupacional e incapacidade laboral, bem como as principais linhas de argumentação, para a descaracterização do nexo causal nos casos em que havia nexo causal presumido pelo critério epidemiológico. Material e método: O material de estudo (83 laudos) foi buscado dentre os processos arquivados no período de 2012 a 2016 na Coordenadoria de Gestão de Arquivo do TRT-2, que abrange 30 municípios da região metropolitana de São Paulo e Baixada Santista. Atributos associados aos grandes temas da pesquisa foram codificados com o objetivo de melhor sistematização para uma análise de conteúdo. Resultados: Os laudos periciais foram elaborados, na sua quase totalidade por médicos, dentre os quais 56 (67,47%) médicos do trabalho, 13 (15,66%) médicos sem especificação de especialidade, 9 (10,84%) médicos com especialização em perícia ou legistas e 4 ortopedistas (4,82%). Um deles (1,21%) foi elaborado por fisioterapeuta. Do total de laudos, 25 (30,12%) não tinham quaisquer informações sobre o processo de adoecimento e apenas 23 (27,71%) contemplaram uma história clínica abrangente. Em 34 (40,96%) não havia qualquer informação sobre as características da atividade de trabalho e em 30 (36,15%) havia a citação de alguns aspectos biomecânicos. Apenas 19 (22,89%) apresentaram uma análise da atividade de trabalho, incluindo aspectos biomecânicos e organizacionais. Nenhum laudo continha uma análise da incapacidade para o trabalho de forma ampla, sendo que em 50 laudos (60,24%), o perito considerou apenas o diagnóstico para se pronunciar sobre a incapacidade. Do total dos laudos, apenas 13 (15,66%) utilizaram o conceito de multicausalidade e 12 (14,46%) o de concausalidade. Dos 15 laudos com nexo causal presumido pelo critério epidemiológico, descaracterizados no caráter ocupacional na perícia, nenhum continha uma análise da atividade de trabalho, embora 9 deles tenham utilizado argumentos biomecânicos, 8 tenham utilizado o argumento de que se tratava de doença degenerativa e 3 de que o quadro era de fibromialgia não ocupacional. Foram discutidos conceitos de adoecimento ocupacional, nexo causal e incapacidade, além da relação de desigualdade, presenteísmo, individualização do adoecimento e culpabilização. Conclusão: A maioria dos laudos periciais peca pela falta de consistência conceitual, metodológica e argumentos fundamentados, deixando lacunas na área clínica, na análise da atividade de trabalho e na avaliação de incapacidade. / Introduction: The Civil Code Procedure determines that in judicial proceedings in which the matter depends on technical or scientific knowledge, the judge will be assisted by experts, who will produce a forensic report. A total of 83 reports, from the Regional Labor Court of the 2nd Region (TRT-2), were analysed, concerning claimants suffering from Repetitive Strain Injury or Work-Related Musculoskeletal Disorders (RSI/WRMD), which include occupational chronic conditions of the musculoskeletal system, that are due, among other reason to the execution of repetitive movements for a prolonged time and static overload without pause foa a physiological recoevery. They should address the various aspects of illness in order to assist the judge in his decision regarding the existence of as aggravated health related to work, as well as its extent and repercussions on the life and work capacity of the worker. Objectives: To identify and analyse concepts about occupational illness and disability to work, expressed in the reports, as well as the main lines of argument, for the de-characterization of the causal nexus in cases where there was causal nexus presumed by the epidemiological criterion. Material and method: The study material was searched from the archived processes from 2012 to 2016 in the File Management Coordination of TRT-2, which covers 30 municipalities in the metropolitan region of São Paulo and Baixada Santista. Attributes associated with the major themes of the research were codified with the aim of better systematization for a content analysis. Results: The expert reports were elaborated almost entirely by physicians, among them 56 (67.47%) occupational physicians, 13 (15.66%) doctors without a declared specialty, 9 (10.84%), forensic doctors, 4 orthopedists (4,82%). One of the reports (1.21%) was elaborated by a physiotherapist. Of the total reports, 25 (30.12%) did not have information about the illness process and only 23 (27.71%) contemplated a comprehensive medical history. In 34 (40.96%) there was no information about the characteristics of the work activity and in 30 (36.15%) there were citation of some biomechanical aspects. Only 19 (22.89%) presented an analysis of the work activity, including biomechanical and organizational aspects. No report contained an embrancing analysis of disability to work comprehensively, and in 60.24% of them, the expert considered only the diagnosis to pronounce on the disability. Of the total reports, only 13 (15.66%) used the concept of multicausality and 12 (14.46%) the concept of concausality. Of the 15 reports with a presumed causal nexus by the epidemiological criterion, which were not characterized in the occupational character, none contained an analysis of the work activity, although 9 of the 15 reports used biomechanical arguments to de-characterize the occupational character, 8 used the argument that it was degenerative disease and 3 that the condition was non-occupational fibromyalgia. Concepts of occupational illness, causal nexus and disability were discussed, as well as the relationship of inequality, presenteism, individualization of illness and blame. Conclusions: Most of the expert reports are lacking in conceptual, methodological and reasoned arguments, leaving relevant gaps in the clinical area, in the analysis of the work activities and in the assessment of disability.

O presente estudo avalia a associação entre estresse no trabalho e auto-relato de diagnóstico médico de lesão por esforço repetitivo (LER). Trata-se de um estudo seccional, inserido no Estudo Pró-Saúde, que consiste no acompanhamento de uma coorte de funcionários técnico-administrativos de uma universidade no Estado do Rio de Janeiro. Os dados foram obtidos, no ano de 2001, a partir da aplicação de um questionário auto-preenchível. A população de estudo constou de 3.314 funcionários, dentre os quais, 485 apresentaram auto-relato de diagnóstico médico de LER, após sua admissão como funcionários da universidade. A prevalência de LER foi maior entre as mulheres (19,4%) do que entre os homens (8,8%). O estresse no trabalho foi avaliado através da versão reduzida do Job Content Questionnaire, desenvolvido por Karasek e Theorell, cujas questões se destinam a avaliar a demanda psicológica, o controle sobre o próprio trabalho e, o apoio social no trabalho. A análise do estresse no trabalho foi realizada de acordo com os quadrantes propostos por Karasek (1979): baixa exigência (baixa demanda e alto controle); trabalho passivo (baixa demanda e baixo controle); alta exigência (alta demanda e baixo controle) e; trabalho ativo (alta demanda e alto controle). Nesta análise, utilizou-se como categoria de referência, a baixa exigência, por compor um cenário ideal de trabalho. Após ajuste por variáveis socioeconômicas e demográficas (idade, escolaridade e renda familiar per capita) e, ocupacionais (anos de trabalho na universidade e ocupação), homens e mulheres com alta exigência no trabalho, apresentaram uma chance maior de serem acometidos por LER (homens: OR= 1,88; IC95% 1,07-3,29 e mulheres: OR= 1,90; IC95% 1,32-2,02). No ajuste adicional pelo apoio social no trabalho, houve redução da força da associação, para ambos os sexos. Para as mulheres com alta exigência no trabalho, esta associação manteve-se significativa (OR= 1,63; IC95%= 1,12-2,37); enquanto que para os homens, esta associação ficou marginalmente significante (OR= 1,62; IC95%= 0,91-2,87). Este estudo reforça que o desequilíbrio entre a demanda psicológica no trabalho e o controle sobre o próprio trabalho é importante na ocorrência de LER e, portanto, pode ser útil na elaboração de medidas preventivas desse crescente problema de sáude pública. Espera-se que as hipóteses geradas neste estudo possam ser testadas em novas investigações que incorporem o desenho longitudinal, como o Estudo Pró-Saúde, no qual este se insere. / The study evaluates the association between job strain and self-reported medical diagnosis of repetitive strain injury (RSI). This is a cross-sectional study, included in the Pro-Saude Study, which consists of tracking a cohort of technical and administrative employees of a university in the State of Rio de Janeiro. The data were obtained in 2001 from the application of a self-administered questionnaire. The study population consisted of 3314 employees, among which 485 were self-reported medical diagnosis of RSI, after this admission to university. The prevalence of RSI was higther among women (19.4%) than amog men (8.8%). Job strain was assessed by the shortened version of Job Content Questionnaire, developed by Karasek and Theorell, whose questions are intended to assess the psychological demands, control over work, and social support. The analysis of job strain was performed according to the quadrants proposed by Karasek (1979): low strain (low demand and high control), passive job (low demand and low control), high strain (high demand and low control) and, active job (high demand and high control). In this analysis, was used as the reference category, the low strain, an ideal setting for composing work. After adjusting for socioeconomic and demographic variables (age, education and family income per capita) and occupational (years work and occupation), men and women with high demands at work were more likely to be affected by RSI (men : OR = 1.88, 95% CI 1.07; 3.29 and women: OR = 1.90, 95% CI 1.32; 2.02). In additional adjustment for social support at work, a reduction in strength of association for both sexes was founded. For women at high strain at work, this association remained significant (OR = 1.63, 95% CI 1.12 to 2.37), while for men, this association was marginally significant (OR = 1, 62, 95% CI 0.91 to 2.87). This study reinforces that the imbalance between job psycological demands and job control is important in the occurrence of RSI and therefore may be useful in developing preventive measures of this growing problem of public health. It is expected that the hypoteses generated in this study can be tested in further investigations that include the longitudinal design, as the Pro-Saude Study, in which it falls.

O presente estudo avalia a associação entre estresse no trabalho e auto-relato de diagnóstico médico de lesão por esforço repetitivo (LER). Trata-se de um estudo seccional, inserido no Estudo Pró-Saúde, que consiste no acompanhamento de uma coorte de funcionários técnico-administrativos de uma universidade no Estado do Rio de Janeiro. Os dados foram obtidos, no ano de 2001, a partir da aplicação de um questionário auto-preenchível. A população de estudo constou de 3.314 funcionários, dentre os quais, 485 apresentaram auto-relato de diagnóstico médico de LER, após sua admissão como funcionários da universidade. A prevalência de LER foi maior entre as mulheres (19,4%) do que entre os homens (8,8%). O estresse no trabalho foi avaliado através da versão reduzida do Job Content Questionnaire, desenvolvido por Karasek e Theorell, cujas questões se destinam a avaliar a demanda psicológica, o controle sobre o próprio trabalho e, o apoio social no trabalho. A análise do estresse no trabalho foi realizada de acordo com os quadrantes propostos por Karasek (1979): baixa exigência (baixa demanda e alto controle); trabalho passivo (baixa demanda e baixo controle); alta exigência (alta demanda e baixo controle) e; trabalho ativo (alta demanda e alto controle). Nesta análise, utilizou-se como categoria de referência, a baixa exigência, por compor um cenário ideal de trabalho. Após ajuste por variáveis socioeconômicas e demográficas (idade, escolaridade e renda familiar per capita) e, ocupacionais (anos de trabalho na universidade e ocupação), homens e mulheres com alta exigência no trabalho, apresentaram uma chance maior de serem acometidos por LER (homens: OR= 1,88; IC95% 1,07-3,29 e mulheres: OR= 1,90; IC95% 1,32-2,02). No ajuste adicional pelo apoio social no trabalho, houve redução da força da associação, para ambos os sexos. Para as mulheres com alta exigência no trabalho, esta associação manteve-se significativa (OR= 1,63; IC95%= 1,12-2,37); enquanto que para os homens, esta associação ficou marginalmente significante (OR= 1,62; IC95%= 0,91-2,87). Este estudo reforça que o desequilíbrio entre a demanda psicológica no trabalho e o controle sobre o próprio trabalho é importante na ocorrência de LER e, portanto, pode ser útil na elaboração de medidas preventivas desse crescente problema de sáude pública. Espera-se que as hipóteses geradas neste estudo possam ser testadas em novas investigações que incorporem o desenho longitudinal, como o Estudo Pró-Saúde, no qual este se insere. / The study evaluates the association between job strain and self-reported medical diagnosis of repetitive strain injury (RSI). This is a cross-sectional study, included in the Pro-Saude Study, which consists of tracking a cohort of technical and administrative employees of a university in the State of Rio de Janeiro. The data were obtained in 2001 from the application of a self-administered questionnaire. The study population consisted of 3314 employees, among which 485 were self-reported medical diagnosis of RSI, after this admission to university. The prevalence of RSI was higther among women (19.4%) than amog men (8.8%). Job strain was assessed by the shortened version of Job Content Questionnaire, developed by Karasek and Theorell, whose questions are intended to assess the psychological demands, control over work, and social support. The analysis of job strain was performed according to the quadrants proposed by Karasek (1979): low strain (low demand and high control), passive job (low demand and low control), high strain (high demand and low control) and, active job (high demand and high control). In this analysis, was used as the reference category, the low strain, an ideal setting for composing work. After adjusting for socioeconomic and demographic variables (age, education and family income per capita) and occupational (years work and occupation), men and women with high demands at work were more likely to be affected by RSI (men : OR = 1.88, 95% CI 1.07; 3.29 and women: OR = 1.90, 95% CI 1.32; 2.02). In additional adjustment for social support at work, a reduction in strength of association for both sexes was founded. For women at high strain at work, this association remained significant (OR = 1.63, 95% CI 1.12 to 2.37), while for men, this association was marginally significant (OR = 1, 62, 95% CI 0.91 to 2.87). This study reinforces that the imbalance between job psycological demands and job control is important in the occurrence of RSI and therefore may be useful in developing preventive measures of this growing problem of public health. It is expected that the hypoteses generated in this study can be tested in further investigations that include the longitudinal design, as the Pro-Saude Study, in which it falls.